-
Notifications
You must be signed in to change notification settings - Fork 0
/
index.js
170 lines (140 loc) · 4.31 KB
/
index.js
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
var Jimp = require('jimp');
var mergeOptions = require('merge-options');
function defaultOption() {
return {
width: 256,
height: 128,
background: { red: 0, green: 0, blue: 0, alpha: 255 },
channel: {
red: true,
green: true,
blue: true
}
};
}
function buildOption(inputOption) {
var option = inputOption;
if (!option || (typeof option !== 'undefined' && typeof option !== 'object')) {
option = {};
}
if (typeof option.background !== 'undefined' && typeof option.background !== 'object') {
delete option.background;
}
return mergeOptions(defaultOption(), option);
}
function generateHistogram(input, output, inputSetting, callback) {
var setting = buildOption(inputSetting);
var rgbData = array256Builder();
Jimp.read(input, function (err, image) {
if (err) {
console.log(err);
return;
}
image.scan(0, 0, image.bitmap.width, image.bitmap.height, function (x, y, idx) {
rgbData.r[this.bitmap.data[ idx + 0 ]]++;
rgbData.g[this.bitmap.data[ idx + 1 ]]++;
rgbData.b[this.bitmap.data[ idx + 2 ]]++;
rgbData.a[this.bitmap.data[ idx + 3 ]]++;
if(x + 1 === image.bitmap.width && y + 1 === image.bitmap.height) {
rgbData.minmax = getRGBMinMax(rgbData);
rgbData.scale = getScale(rgbData.minmax.bound, setting.height);
rgbDataToHis(rgbData, setting, function(outputJimp) {
outputJimp.write(output, function() {
if (typeof callback === 'function') {
callback();
return;
}
});
});
}
});
});
}
function getRGBMinMax(rgbData) {
var minmaxData = {
r: getMinMax(rgbData.r),
g: getMinMax(rgbData.g),
b: getMinMax(rgbData.b),
a: getMinMax(rgbData.a)
}
minmaxData.bound = getMinMax([0, minmaxData.r.max, minmaxData.g.max, minmaxData.b.max]);
return minmaxData;
}
function getScale(boundData, height) {
var output = height / (boundData.max || 1);
return Number(output.toFixed(4));
}
function getMinMax(colorArray) {
return { max: Math.max.apply(null, colorArray), min: Math.min.apply(null, colorArray) }
}
function getDrawLimit(colorData, scale) {
return colorData * scale;
}
function gertColorValue(channelActive, VerticalLimit, horizonLevel) {
if (!channelActive || VerticalLimit <= 0) {
return 0;
}
if (VerticalLimit >= horizonLevel) {
return 255;
}
return 0;
}
function numberCheck(input, fallback) {
if (typeof input !== 'number') {
return fallback;
}
return input
}
function buildIntHex(channel, rVertical, gVertical, bVertical, horizonLevel, background) {
var red = gertColorValue(channel.red, rVertical, horizonLevel);
var green = gertColorValue(channel.green, gVertical, horizonLevel);
var blue = gertColorValue(channel.blue, bVertical, horizonLevel);
if (red + green + blue === 0) {
return Jimp.rgbaToInt(numberCheck(background.red, 0), numberCheck(background.green, 0), numberCheck(background.blue, 0), numberCheck(background.alpha, 255));
}
return Jimp.rgbaToInt(red, green, blue, 255);
}
function rgbDataToHis(rgbData, setting, callback) {
var w = setting.width
var h = setting.height
var horizonLevel = 0;
var tempHex = null;
var rVertical = 0;
var gVertical = 0;
var bVertical = 0;
var imageOutput = new Jimp(setting.width , setting.height, 0xFFFFFFFF, function (err, image) {
if (err) {
console.log('Jimp create image error: ', err);
}
});
for(var verticalIndex = 0; verticalIndex < w; verticalIndex++) {
rVertical = getDrawLimit(rgbData.r[verticalIndex],rgbData.scale);
gVertical = getDrawLimit(rgbData.g[verticalIndex],rgbData.scale);
bVertical = getDrawLimit(rgbData.b[verticalIndex],rgbData.scale);
for( var horizonIndex = h-1; horizonIndex >= 0; horizonIndex--) {
horizonLevel = h - horizonIndex;
tempHex = buildIntHex(setting.channel, rVertical, gVertical, bVertical, horizonLevel, setting.background);
imageOutput.setPixelColor(tempHex, verticalIndex, horizonIndex);
if (verticalIndex+1 === w && horizonIndex === 0) {
if (typeof callback === 'function') {
return callback(imageOutput);
}
}
}
}
}
function array256(default_value) {
var arr = [];
var i = 0;
for (i = 0; i<256; i++) { arr[i] = default_value; }
return arr;
}
function array256Builder() {
var output = {};
output.r = array256(0);
output.g = array256(0);
output.b = array256(0);
output.a = array256(0);
return output;
}
module.exports = generateHistogram;